APRIL 7: After opening the season on the injured list due to a shoulder problem, Athletics closer Trevor Rosenthal could now require thoracic outlet surgery to address the injury, manager Bob Melvin announced to reporters Wednesday (Twitter link via Shayna Rubin of the San Jose Mercury News). It’s a sudden and troubling development for a struggling A’s club. The procedure would come with “at least” a 12-week recovery time, Matt Kawahara of the San Francisco Chronicle tweets. The right-hander is weighing his options and is expected to make a decision in the near future.

Rosenthal, 30, spent much of the offseason seeking a lucrative multi-year deal after turning in an absolutely dominant performance between the Royals and the Padres last season. However, when he wasn’t able to find a long-term deal to his liking, the hard-throwing righty opted for a one-year deal at a strong $11MM rate to serve as the closer at the pitcher-friendly O.Co Coliseum.

It was a surprise investment for an A’s club that spent most of the winter idling on the sidelines as teams throughout the league sifted through the free-agent market. Only after the A’s were able to shed a notable portion of Khris Davis’ contract did they enter the free-agent waters, and even then, their initial expenditures were modest, one-year commitments to Yusmeiro Petit, Sergio Romo and Mitch Moreland. Rosenthal was an entirely different type of spend, and it’s now an open question whether they’ll get any real return on what was a major splash by their standards.

Thoracic outlet syndrome is the latest in a series of setbacks for Rosenthal, who broke into the league as one of the game’s most dominant young relievers with the Cardinals but has since struggled to stay healthy. Tommy John surgery wiped out Rosenthal’s entire 2018 season, and when he returned with the Nationals in 2019, he developed a sudden case of the yips. Rosenthal walked 26 of the 85 batters he faced between Washington and Detroit that season. He also hit another four batters and snapped off nine wild pitches in just 15 1/3 innings. He tried to find himself with the Yankees’ Triple-A club but faced just five hitters with Scranton, issuing three walks, hitting a fourth batter and throwing another wild pitch.

Those immense struggles made Rosenthal’s comeback in 2020 all the more remarkable. Not only did he rediscover some big league success, he emerged as one of the most dominant relievers in all of baseball. Through 23 2/3 innings between Kansas City and San Diego, Rosenthal notched a 1.90 ERA with an overpowering 41.8 percent strikeout rate, a strong 8.8 percent walk rate and a fastball that averaged 98.1 mph. It was vintage Rosenthal.

From here, the future is sadly muddied once again. The track record for pitchers coming back from thoracic outlet surgery is generally poor, and few pitchers have undergone both Tommy John surgery and a TOS procedure in such close proximity. Matt Harvey is the most prominent example of a pitcher to undergo both operations in a short time, missing the 2014 season due to Tommy John and then undergoing TOS midway through the 2016 campaign. Obviously, he’s been unable to rediscover the dominant form he displayed early in his career.

There are certainly success stories among pitchers who’ve had surgery to correct thoracic outlet syndrome. Recently retired righty and current Rangers general manager Chris Young credited the procedure with saving his career, and Rosenthal’s former Cardinals teammate, Jaime Garcia, enjoyed a productive three-year stretch upon returning from his own TOS operation.

For the Athletics, the new development on Rosenthal means they’ll be extra reliant on veterans like Romo, Petit and Jake Diekman in the late innings. Right-handers Lou Trivino and J.B. Wendelken have had their share of success in the big leagues as well; Wendelken in particular has been quietly dominant dating back to 2018. The A’s also have a former top 10 overall pick, left-hander A.J. Puk, as an intriguing option in the ’pen this year as he looks to put his own injury woes in the rearview mirror.

Major League Signings

• Mitch Moreland, 1B/DH: One year, $2.25MM ($225K available in incentives)
• Trevor Rosenthal, RHP: One year, $11MM ($3MM paid in 2021, $3MM in 2022, $5MM in 2023)
• Sergio Romo, RHP: One year, $2.25MM
• Mike Fiers, RHP: One year, $3.5MM
• Yusmeiro Petit, RHP: One year, $2.25MM ($450K available in incentives)
• Total spend: $21.25MM

Trades and Claims

• Acquired LHP Adam Kolarek and OF Cody Thomas from the Dodgers for 3B Sheldon Neuse and RHP Gus Varland
• Acquired SS Elvis Andrus and C Aramis Garcia from the Rangers for LF Khris Davis, C Jonah Heim, and RHP Dane Acker.
• Acquired LHP Nik Turley from Pirates for cash considerations (later lost on waivers to White Sox)
• Acquired LHP Cole Irvin from Phillies for cash considerations
• Selected OF Ka’ai Tom from Indians in Rule 5 draft
• Selected RHP Dany Jimenez from Blue Jays in Rule 5 draft (later returned to Toronto)

Notable Minor League Signings

• Domingo Acevedo, Cristian Alvarado, Argenis Angulo, Matt Blackham, Reymin Guduan, Deolis Guerra, Montana DuRapau, Pete Kozma, Jed Lowrie, Frank Schwindel, Trey Supak, Jacob Wilson,

Extensions

• None

Notable Losses

• Jake Lamb, Marcus Semien, Tommy La Stella, T.J. McFarland, Robbie Grossman, Liam Hendriks, Mike Minor, Joakim Soria

Of all the players set for free agency after the 2020 season, A’s shortstop Marcus Semien was a particularly interesting case. The A’s somewhat surprisingly chose not to extend him a qualifying offer. In doing so, they signaled three things: 1.) They believed Semien might accept the $18.9MM qualifying offer; 2.) They were unwilling to pay him that sum; 3.) They were prepared to enter 2021 with a new shortstop. Ultimately, Semien signed a one-year deal below the QO value to play for the Toronto Blue Jays, and the A’s received nothing in return.

The very same day that Semien’s accord was announced, double-play partner Tommy La Stella signed a three-year deal with the Giants. La Stella’s time in Oakland was brief, but he was critical for the team down the stretch after coming over in a trade with the division-rival Angels. He slashed .289/.369/.423 in 27 regular-season games from the top of manager Bob Melvin’s order. Acquiring that performance came only at the cost of erstwhile top prospect Franklin Barreto. The goal is not to pay for past performance, however, nor for past value, so the A’s said their thank-yous and let La Stella move across the Bay at the reasonable AAV of $6.25MM per season.

At that point in late January, Liam Hendriks had already inked his new deal with the White Sox. Even Robbie Grossman had long since found his new home in Detroit. In Oakland, however, the winter was (again) in danger of being defined by the players lost in free agency. Executive vice president of baseball operations Billy Beane and general manager David Forst are as cold-blooded as they come, however. They were no doubt aware that something like, say, not having a middle infield would temporarily leave them in ill-favor with the public, but the end goal was not to have a middle infield in January. The A’s are generally at a disadvantage when it comes to resources, but they had as much time at their disposal as the other 29 teams, and they used it to enact a coherent offseason strategy.

On Feb. 6, the A’s offseason began in earnest. They and another division rival, the Rangers, completed an outside-the-box five-player swap centered on two out-of-favor veterans on hefty contracts. In its most basic form, the trade sent Khris Davis, Jonah Heim, and Dane Acker from the A’s to the Rangers for Elvis Andrus and Aramis Garcia.

For the A’s, this deal enabled them to shift money around. Oakland fell in love with Davis’ light-tower power, but he slumped to an 82 wRC+ over the past two seasons. Davis started only 14 games in the field going back to 2018, so if he doesn’t create value with his bat, he doesn’t create value. And yet, in the second year of a two-year extension signed prior to 2019, Davis would account for almost 20 percent of a payroll that was already without much margin for error. Turning that dead money into two years of a serviceable shortstop may end up as a decent sleight of hand on the A’s part.

Of course, Oakland had to give up more than just Davis. Heim has promise – Fangraphs gives him a 40+ future value score- but he’s also a 25-year-old backup at a position of organizational depth. If Garcia can’t step directly into Heim’s shoes as Sean Murphy’s backup, then Austin Allen can. Allen, though 27 years old, was actually ranked a spot above Heim in Fangraphs’ organizational prospect rankings entering 2020. The A’s are taking on some risk here, as Garcia and Allen profile similarly as bat-first backstops; furthermore, if Murphy goes down for any extended period of time, they might have preferred Heim’s defensive skill set as a long-term stand-in. But if all goes according to plan, Murphy will shoulder the load. In that case, either Garcia or Allen ought to suffice as a backup.

Acker is the true cost of doing business. He’s a durable college arm with a repeatable, clean delivery and a decent chance of making it to the Majors. He’s also a 2020 draft pick who has yet to make his professional debut. The A’s essentially had to tack on a fourth-round pick to make this deal work. All things considered, that’s hardly a backbreaking tax to burden when slashing $9.5MM off the payroll.

The crux of this deal comes down to whether or not you believe in Andrus as a two-year stopgap. His defensive metrics are all over the place, though it won’t hurt to play alongside Matt Chapman. Offensively, Andrus was a 76 wRC+ hitter in both 2018 and 2019. He admits to being slow to adapt to modern analytics at the plate. That makes him an interesting fit in Oakland. If he’s ready to change his approach, maybe the A’s feel they can unlock something for him, though the Coliseum is notoriously tough on right-handed hitters. With a lifetime .098 career ISO and groundball-heavy approach at the plate, he may have trouble hitting any of these new baseballs out of that yard.

For what it’s worth, ZiPS projects Andrus to re-spawn as a 1.2 fWAR player, which is roughly his production in each of 2018 and 2019. It’s probably safest to assume he can be a 1-2 WAR player, which makes his dollar count about right. Whether or not he can sufficiently replace Semien depends on which version of Semien you’re imagining. If it’s the 2019 version that notched 8.9 bWAR/7.6 fWAR, you can forget about it. But if you’re thinking about the 2020 guy who put up numbers that extrapolate over a full season to 1.35 bWAR/3.24 fWAR, well, now we’re getting somewhere. Andrus is not the ideal shortstop, but at $7.25MM per season for two years, he’s a better use of the money than Davis would have been. That’s the calculus that makes this deal work – if it works.

With the money saved, Beane and Forst went on a mini spending spree of their own. They brought back Mike Fiers just hours after the Andrus trade. They essentially replaced Joakim Soria with Sergio Romo on Valentine’s Day, re-signed Yusmeiro Petit five days after that, and capped their bullpen revamp with a big-ish fish in Trevor Rosenthal, whom they signed to a much-deferred one-year, $11MM pact.

Romo provides insurance for the bullpen, as does Fiers for the rotation. Neither hurler is a place to be a bell-cow arm, but they are trustworthy enough to hold the line. On the whole, the A’s free agent class would have been a real get after 2013. Present day, it’s not as splashy as, say, the White Sox, who signed Hendriks, but it could nonetheless be impactful. Rosenthal seemed to put himself back together in 2020 with 11 saves and a 1.90 ERA/2.22 FIP across 23 2/3 innings. He stuff is electric, and his walk rate returned to a palatable 8.8 percent. His 2019 wildness is looking less like decline and more like re-calibration after Tommy John surgery.

Of course, where in most cases we’re willing to throw out 2020’s numbers because of the pandemic, it’s a little convenient to take Rosenthal’s performance as proof of concept. Admittedly, then, there’s risk. Still, Rosenthal has 92 more career saves than Hendriks, he’s less prone to giving up home runs (6.4 percent HR/FB for Rosenthal to 10.2 percent HR/FB for Hendriks), and Rosenthal has a lower career ERA, FIP, xFIP, and SIERA. Hendriks outdoes Rosenthal in terms of control, and he does have two insane seasons out of the last two compared to one for Rosenthal.

Put aside all the noise of career numbers and Rosenthal’s messy 2019, and give in to last season’s numbers as the real McCoy just for a second. Rosenthal put up 1.1 bWAR to Hendriks’ 1.3 bWAR. Rosenthal had a 35.2 percent CSW (called strike plus whiff rate) compared to 31.0 percent for Hendriks. Rosenthal finished in the 99th percentile for fastball velocity, xERA, xBA, strikeout rate, and xwOBA. You barely even have to squint to consider Rosenthal a lateral move at worst (without the long-term financial commitment).

The A’s largely stuck with their internal options to replace La Stella at the keystone. Tony Kemp and Chad Pinder splitting time in a straight platoon is one potential eventuality. To open the season, however, it’s looking like old friend Jed Lowrie will share the middle infield with Andrus in his third tour of duty with the A’s.

The only Major League contract they gave out to a hitter this winter went to Mitch Moreland. The 35-year-old has only once produced more than 1.0 fWAR in a season, which is fairly stunning given that he’s now been in the bigs for 11 years. But he’s trending up over the last three seasons, especially in his specialty department (vs. RHP): 106 to 125 to 146 wRC+ from 2018 to 2020. He has enough glove to insure Matt Olsen at first, but given Olsen’s own glovework, Moreland’s only real job is to rake. In 2020, that’s exactly what Moreland did: .265/.342/.551, 135 wRC+, 10 home runs, a solid 21.1 percent strikeout rate, 9.9 percent walk rate, and .287 ISO.

Cot’s contracts pegs the A’s payroll to be $83.5MM by raw dollars, $100MM on the dot as far as the luxry tax is concerned. They’ll pay out even less than that because Rosenthal will receive just $3MM in 2021. Regardless, the A’s payroll is closer to zero than it is to the first tax threshold of $210MM. They’re about $11MM under their full-scale payroll from 2020, and if they remain at this current level, it’ll be their lowest payroll since 2018. They have occasionally taken on in-season money in the $10MM range, but they’re more likely to add $1MM-3MM, or even further diminish the payroll should things go sour. Oakland excels at identifying its weaknesses and finding reinforcements throughout the season in this way. Jake Lamb, Mike Minor and La Stella were the guys last year, and the A’s will probably look at that class of player again.

To accomplish that slimming of the payroll, Beane and Forst helped themselves with some low-cost additions to fill out the roster. Ka’ai Tom was a Rule 5 Draft selection from the Indians, and he’ll enter the season as their fourth outfielder. Pinder and Kemp are also capable of defending the grass, but Tom does provide left-handed balance to the A’s trio of right-handed starters: Ramon Laureano, Stephen Piscotty, and Mark Canha.

Skeptics might wonder why Tom would be left unprotected by a Cleveland organization that’s perpetually in desperate need of outfielders, and that’s a fair question. He’s undersized at 5’9″, almost 27, and only once ranked in Baseball America’s top 40 Indians’ prospects (No. 31 in 2016). His physical skills in terms of speed and power aren’t immense, but he’s succeeded at every level thus far, including a .298/.370/.564 line (132 wRC+) in 211 plate appearances at Triple-A in 2019.

If Tom is the “overlooked” brand of undervalued asset, former Ray and Dodger Adam Kolarek qualifies as the “specialist.” The southpaw is cost-efficient with four years of control remaining, he limits free passes (6.0 percent walk rate for his career), he gets the ball on the ground at a 62.7 percent clip, and he’s death to lefties, who hit just .176/.217/.248 off him.

The A’s biggest need this offseason might have been health, particularly in the rotation. Oakland’s starting staff can be the backbone of a contender. If Chris Bassitt and Fiers can excel in the Coliseum, so should Jesus Luzardo, A.J. Puk, Frankie Montas, and Sean Manaea. But health has been an issue, and the A’s will continue to manage the workloads of their young arms as they try to readjust to the slog of a 162-game season.

If you’re of the camp that thinks the A’s took a step back during the winter, it’s not hard to understand why. But the Astros took a step back too, the Angels face many of the same roster questions as usual, and the Mariners and Rangers have a ways to go before closing the gap. There’s reason to hope for a fourth consecutive playoff appearance out of Oakland. If it happens, it will be driven by Melvin’s ability to mix and match and get the most out of an imperfect roster. A return to health for Chapman and breakout seasons on the mound from Luzardo, Montas, and/or Puk wouldn’t hurt either. But those aren’t things you can secure in the offseason.

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